Lbottow



0. B. CAMP.

FULLERING BLOCK FOR ROCK DRILL BITS.

APPLICATION FILED JULY 24| 1917.

.Patentedmg 5, I9I9.

ou an or' nisi-entraran,l CALIFORIA, Ansinnen or one-nenn Toner a.

LENNN, F ENG-ELMINE, 'CLlFORNI .To all whom it may concern.' I Be itknown 'that l, ORRIN B. CAMr, a c1t1- zen of the United tate's, residingat Engelmine, in the county of Plumas and Statel of California, haveinvented new and use-` ful llmprovernents in Fullering-Blocks forRoclrfDrill'Bits, of `which the following is a specihcation( 1 'lheob'ect of the present invention is tof provide a'device for swaging,sizing and fullering drill bits,

Means for sharpening Carrbits, used with drills, Vhave heretoforecomprised only a block for swagin thebita block. for sizing it, and adie for orming the edgeA of ther-bit. llln, order to obtain sharpcornerson the ,bit it has heretofore been necessary/,"withfthe tools at resenton vthe market, first, to swage theibit etween'a 'pair ofswagin'g'blocks, lthen to size it between a pair of sizin bloote, andthen to press the end of the bit against ay die. Butwhilethis'processwould cause the-edge of the bit to correspond in aycertain degree with the formof the die, yetv yit would onlydo so to alimited extent at -thecorners of the bit;z Conse uently, it has y beennecessary to 1re-heat the it and repeat i the process until finallythedie was" provided with sharpcorners at its biting or cut 3U tingedge. 'lhe object of the. presentinvention "is to *ferm4 the bitwith'sharp corners by-drawing l et or fullering its'corners.

lln the present invention l use only two blocks, namely, 'an upperbloot` and a lower bloclr, not only for swaging and sizing, but

also for fullering', that is, for drawing out i the corners of the bitso as to provide the bit i y with a sharpedge along its whole length.

y 3 'is `a bottom view of the `upperbloek;Fig..4 LiI is' a'vlongitudinal section through the t5 l ln the accom anying drawing,Figurel is a perspective view of in improvedblocks lFig.. 2 is a planview of t e lower block; Fig..

eferring to the drawing, 1 indicates; an

' upper block, and 2 aI lower block, of -a` pair per swaging surface 3for thegreater part of its depth, its rear end terminating in anupwardly and rearwardly sloping surface 4.

i The lower block l Specification of Letters Patent. 2 Patented Aug, 5,1919..A `application mea July a4, im?. serial 160.1132148. 4

ln one direction said upper surface extends other direction islimited bya vertical wall 6, and the upper surface 10 of the lower block behindsaid sloping surface l is Hush with the top of .said wall. ln likemanner the to the end of the lower block, and in the corresponding endof the upper block 1 has a swinging-,surface l'which is datV and eitheswaging ing at'the rear end tapering and constituting y,

partof the block, that is to say,

esV

theend of the bit is received, said cavity be whena bit is placedbetween said portions o f the up er and lower blocks, in a heated and.there ore slightly plastic condition, and

the upper block is" pressed 'down upon the V lower block, the result' isto squeeze the bit downward and also to form' `a tapering end thereon,this being formed'by the two surfaces l and 9, against which the ven dofthe bit is squeezed.

The other ends blocks 1, l2, constituteI fullering portions. hasvat itsleft hand end, `as

Vof the upper vand lower seen-in Figs. 1, 2,-a dat portion 12, which isV triangular in shape and is limited at the end of the block by a highwall 13 extending `along the end of the block and on the right hand sideby a sloping surface 141. ln like mannerjthe upper' block is formed withthe dat surface 16 and a sloping surface 17 lirnit ing the flat surfaceon one side; '0n the .other side ofsaid Hat surface is a de pression ormortise 18, in which the upper edge of the wall 13 lits. There is thus.a cavity which-is tapering or beveled on its right hand side and thewidth of which varies according to its `distance from the front end.After swagin `the bit in the manner just above describe f the bit isplaced on the .lower block until its right hand corner rests upon thesloping surface 14 and then the upper bloclr` is brought down onit,thereby fullering or drawing out the right hand corner or end of theedge of the bit. When this has lbeen done it is turned over l'so thatthe same operation is performed on the other end of the bit. ln

1- formed,' whe'n said upper and lower blochs 'i are' fitted together,

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this manner the endsl of the edge of the bit are fullered or drawn out.

Both the lower and upper blocks are formed with registering conicalrecesses, the lower block with a recess 19 and the upper block with arecess 20, These recesses lie immediately to the left of the walls 6 and8 respectively, which walls'therefore extend obliquely across theblocks. These recesses constitute the sizing part of the block, and

the bit is placed in said recesses and said blocks are pressed togetherin order to cornpress the corners to the correct gage to reduce the bitto the proper size to be afterward treated by the dolly in the die. Thewall 13 is of great importance, for it fits in the mortise in the upperblock and prevents the bit from slipping away from the sloping surfaces4, 9, which it tends to do by reason of its being pressed between saidsurfaces.

' I claim:

Means for fullering a corner of a drill bit having two beveled cuttingsurfaces, coinprising two blocks, each havin a depressed, flat, 'swagingsurface, one o said blocks having a wall o1' stop, an inner side ofwhich is at right angles to the swaging surface of the block and theother having a mortise into which the upper portion of the block fitstightly, said blocks also having surfaces sloping upwardly from saidswaging sur- `faces at an acute angle, the longitudinal directions ofsaid sloping surfaces making an acute angle with said wall.

ORRIN B. CAMP.

